This applet will calculate the planetary positions, ascendant, nakshatra, navamsa placement, and vimshottari dasha periods for any time, according to Lahiri ayanamsa. It also draws a simple representation of the Rashi chart. Planetary positions in the Rashi chart are not degree-accurate, but simply reflect house placement. Rahu and Ketu positions are mean or average positions.

28.8 download time is about 30 seconds.

How to Use RishiCalc:

Enter hours as 0 - 23.

Use negative values for Western time zones, e.g.:

EST: -5

CST: -6

MST: -7

PST: -8

All time zones east of Greenwich are positive.

Don't forget to click on the Daylight Savings Time box ("dst") for a daylight savings time chart in order to get the correct time calculation.

Longitude and Latitude must be filled in for the applet to function. If you don't know the longitude and latitude of a city or place, the best online resource is Astrodienst. It will also tell you the proper time zone to use.

Remember that for Western (i.e. positive) longitude values, the time zone offset value must be entered as negative. When the Eastern longitude box is checked, the time zone offset value must be positive. Any other values are a mistake, and give an error.

NOW button gives current time, date, and zone from your local system clock.

CLEAR button clears all fields; resetting RishiCalc for a new calculation.

CLOCK button makes RishiCalc continuously update (every second) until stopped. You must have all the fields filled in properly for this to work. Click NOW and then fill in the longitude and latitude.

STOP stops the clock.

CALC button calculates a chart. Remember: no chart will be calculated if any field is empty.

Notes on Accuracy

Angel21's RishiCalc applet can be counted upon to give good values for the planetary longitudes (usually +/- 2 arcminutes). The ascendant algorithm is highly accurate (thanks to Brian Conrad of JyotishTools - he also provided the Lahiri algorithm, which is good, too!) This means that RishiCalc is useful for most common jyotish applications.

Future Features

This applet is currently under construction, pretty much day by day as time is available. Improvements since RishiCalc first appeared here include:

I am very open to your feedback on this free applet feature from Angel21: emailLet me know how it works for you and which features you would like to see added. Also, since this is a test version, please report any bugs you may find.

To participate in discussion and exchange of astronomy and astrology programs and ideas, go to the AstroJava page.

Angel21's RishiCalc is offered free, for your entertainment. Absolutely nothing is guaranteed or implied about its functionality or internet uptime. Angel21 may discontinue offering the RishiCalc service at any time.